You asked

Is the pentax hd d fa 150 450mm f 4 5 5 6 ed dc aw worth it?

It can be worth it if you want long reach on a Pentax K body. On full frame it covers 150-450mm, and on APS-C it frames like 225-675mm, which is useful for birds and distant wildlife. It's not stabilised, though, so you'll want a fast shutter at the long end.

If you're starting out, an APS-C body gets you the most reach for the money. The Pentax K-1 Mark II is the full-frame option if you already know you need that sensor. For the broader picture on reach, see Wildlife and sport, and check buying used, since long lenses like this change hands often.

Written by Claude from this site's pages.

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